1998 Es300 Idle Issue

[reykay]

This only happens after about 15-20 minutes at a constant speed (such as in cruise control) - at say 75mph. When I slow down to pull of the highway, the car idles very rough - almost stalls. If I take off again and punch the accelerator (around 5-6000rpm), everything is fine. No check engine lights, etc. It's almost like some kind of intake or carbon build-up issue, because a quick punch clears things up.

Anything anybody can suggest would be appreciated.

[juno_reaction]

most likely your air intake. I had something of a similar problem.

[djspawn00]

Clean your throttle body, check your fuel filter, and a seafoam treatment probably wouldn't hurt either. any cel light?

[reykay]

most likely your air intake. I had something of a similar problem.

Thanks for the reply. How did you correct the intake problem?

most likely your air intake. I had something of a similar problem.

Thanks for the reply. How did you correct the intake problem?

Clean your throttle body, check your fuel filter, and a seafoam treatment probably wouldn't hurt either. any cel light?

What's a seafoam treatment? Thanks.

[Eric Cheung]

Could be the IACV (Idle Air Control Valve) having carbon built-up. Cleaning it could solve the problem. Search "IACV" and you should have the details in doing that.

[juno_reaction]

You can buy the air intake tubing off of the internet, install it yourself and save yourself a good 400-600 dollars (what I paid to have mine replaced). Or you could have it taken to a shop and they'll do it for you for the 400-600 dollars. Usually when its the air intake tubing it just means that its either loose or there are a few cracks in the actual tubing. This could result in loss of air to the engine thus causing your "stalling". I'm not too sure about this, but thats what my mechanic told me. I also found some of this out through the website; it seems alot of people have the same problem or something similar to it. Good luck!

[djspawn00]

Seafoam is one of those miracle products in a can but unlike most other products it gets decent results. It cost about $6 a can at most auto stores you'll find tons of threads detailing if you do a search on the forums.

[steviej]

Could be the IACV (Idle Air Control Valve) having carbon built-up. Cleaning it could solve the problem. Search "IACV" and you should have the details in doing that.

BINGO!!!

The symptoms you describe, reykay, are classic for a dirty IACV. Clean it or replace it.

steviej

[reykay]

Thanks all. Finally found the problem. It was the EGR. Replaced it and all hesitation problems are gone. I also understand the EGR's are an issue with '98 ES300's

[mburnickas]

Thanks all. Finally found the problem. It was the EGR. Replaced it and all hesitation problems are gone. I also understand the EGR's are an issue with '98 ES300's

Just gonna say my 98 did the sameting about 2 years ago. New EGR by Lexus (CPO) all good!I think they only las tlike around 70K on this model (year).

[johnrider]

I just want to add that I, too, have a 98 ES300 (70,000 miles) with the same intermittent idle problem when slowing down after driving at highway speeds. It was driving me crazy until I read your posts. I had the EGR valve replaced and it solved the problem. Thanks folks!